1. Field of the Invention
This invention relates to the manufacture of a dynamic random access memory (DRAM), and more specifically to the formation of a DRAM bit line and bit line contact structure.
2. Description of the Prior Art
In the manufacture of semiconductors, conducting wires and conducting wire contacts are used in large quantities. In DRAM manufacture, a contact window is formed in a cell structure, in which a polycrystal material is filled to form a plug, and the chemical mechanical polishing (CMP) is performed to constitute a bit line contact. The structure obtained from this stage is substantially similar to that in FIG. 2a. In the current manufacture process, however, the bit line contact formed has a large contact area. With DRAM becoming more and more compact, the interval between bit lines becomes narrower and narrower. Referring to FIG. 1, when the bit line contact 12 has a large contact area, the bit line 11 has a poor coverage to the bit line contact 12. If one bit line is slightly inclined, it is likely to cause an improper bridging, leading to an abnormal short circuit between bit lines. Therefore, a solution is needed to overcome this problem.